1.虚拟条件句
①现在
If I had time,I would go to shanxi to see the 11th National Games.如果我有时间，我就会去陕西看第十四届全运会。
从句谓语形式：动 词 的 过 去 式 (be 用 were)
口诀：主过从过
②过去
If it had not rained so heavily yesterday,we would have watch Mulan.昨天如果没下大雨的话，我们就看了《花木兰》了。
从句谓语形式：had + 过去分词
口诀：主过完从过完
③将来
If it rained/should rain/were to rain tomorrow,we would change our plan.
如果明天下雨了，我们就更改计划。
从句谓语形式：动 词 的 过 去 式 /should + 动词原形 / were to+ 动词原形
口诀：主过将从should / were to
注意：虚拟语气的世界里没有 was
④错综时间条件句
If I had followed the father’s advice,I would be quite all right now.
如果我当时听爸爸的话，我现在就会好了。（从句说过去，主句说明现在，从句和主
句的形式与各自时态的条件句一致）
2.命令类
I suggested that she（should）visit her parents.
我建议她应该看看她的父母。
表达和建议、要求、命令、主张等含义相关的名词性从句，一律用主语+should+动词原形（should可以省略）结构。具体涉及到这些动词以及它们的名词形式：
一坚持：insist（表要求时才用虚拟语气）
二命令：order, command
三要求：require, request, demand
四建议：suggest, advise, propose, recommend
3.虚拟语气用在状语从句中的应用
①as if / as though 仿佛/好像 从句谓语使用虚拟语气，降时态
He talks as if he knew all about it.
他说起来好像知道这件事的全部一样。
②It’s high/about time that+定语从句 从句谓语使用过去式或者should+原形
It’s high time that we discussed/should discuss who to do it.
我们是时候去讨论一下谁来做这件事了。
③even if / even though 尽管 从句谓语使用虚拟语气，降时态
Even though she had been here very soon,she would not catch the plane.
尽管她很快就到这儿，她也赶不上飞机。
4. wish /if only 如果...就好了
If only I were an adult.如果我是成年人就好了。
I wish she could love me. 如果她爱我就好了。
5.should / would like to have done,was/were to have done,was/were supposed to have done,had better have done,would/had rather have done等结构表示“本想、本该做而未做成”。
I would like to have gone with you,but I have no time.
我本来想和你一起走，但没有时间。
主过从必过这个口诀用于宾语从句中，因为宾语从句要求主从句时态一致（特殊情况除外）。所以也有这样一种说法，就是“主过从四过”。
